Dark matter properties detected using VLT

A recent study using the VLT array has measured the temperature and size of dark matter clumps. Interestingly enough, the study has not yet been submitted to Arxiv, but will probably appear within a week. It is expected to be one of the most important papers in 2006. Here is a teaser:

A recent study using the VLT array has measured the temperature and size of dark matter clumps. Interestingly enough, the study has not yet been submitted to Arxiv, but will probably appear within a week. It is expected to be one of the most important papers in 2006. Here is a teaser:

this was posted on Arxiv around 8 February which was about the same time that the "out of the cold" BBC article quoting Gilmore was posted.

I have a vague memory of discussing this with Spacetiger, a couple of weeks ago, and maybe you also were in that thread. It was about the BBC article you mention.

The thing was they inferred that the DM particles were going around 9 kilometers per second, because they didnt find clouds smaller than a certain size, and the size of the clouds was inferred from the clumps of VISIBLE matter-----the dwarf galaxies

Gerry Gilmore's Cambridge team did a survey of clouds of dark matter, using several telescopes including VLT in Chile. they found no blobs of DM smaller than about 30 million solar masses, or less than 1000 lightyear diameter.

They inferred from this a characteristic TEMPERATURE of dark matter. the particles must be moving on average 9 kilometer per second, so that clouds that are not big enough DISPERSE by random motion.

The clouds that are not big enough don't have enough gravity to hold themselves together, given the particles' speed of random motion.

Spacetiger had some things to say, I think you also commented, and several other people